Conspiracy theories are comforting. In a “shades of gray” world they hold out the prospect that there is a black and white explanation for why things go wrong.

For example, Kennedy did not die because Secret Service incompetence allowed an assassin to get a firing position overlooking the presidential motorcade. No, he died because a secret star chamber of the CIA, the Mafia and Russian intelligence decided he was a threat to their control of the planet and had him executed.

And we did not invade Iraq in search of non-existent WMD because of botched analysis and political interference in the intelligence process. No, the invasion was part of a secret plan by U.S. oil companies to seize Middle East oil.

And President Obama does not pursue his tortured Middle East policy because he is naïve, lacks foreign policy experience, and does not grasp the magnitude of dangers posed by Iran and Sunni terrorists. No, he does it because he was really born in Kenya, he’s a secret Muslim and he wants to transform “Christian” America into an Islamic State.

It is the same with 9/11.

The truth is that we suffered the worst terrorist attack on U.S. soil on September 11, 2001, because successive administrations, Democratic and Republican, failed miserably in their responsibility to defend America.

In 1998, two U.S. embassies were blown to pieces by al Qaida. Our retaliation was pitiful.

We launched Tomahawk missiles at hillsides in Afghanistan, did no harm to the terrorists who had attacked us, and went back to sleep.

In 2000 al Qaida almost sank the USS Cole. Thirty-seven sailors died. Again, we did nothing. We reacted as if the attack had never happened.

Then Bill Clinton left office and George W. Bush replaced him. Eight months passed and again there was no change in posture or policy. We continued to ignore the growing threat, and almost three thousand people paid the price.

So now we have another conspiracy theory. The Saudi government planned, financed and directed 9/11. We did not fail to exercise the vigilance required in a dangerous world — no, we were betrayed. No one could have foreseen or guarded against it.

Hence the Justice Against Sponsors of Terrorism Act (JASTA) bill was unanimously passed by the Senate and now sits in the House.

JASTA is aimed at allowing American citizens to sue foreign governments who have sponsored a terrorist act that harmed them. It makes no reference to 9/11, but its supporters made no secret of the fact that the bill was written to allow individual Americans to pursue legal action against the Kingdom of Saudi Arabia.

Their theory is that the Saudi government was responsible for the 9/11 attacks.

True, the Saudis do deserve criticism. They have been slow to end their dangerous relationship with radical Wahhabi clerics. They have moved too slowly to interdict money moving from the kingdom into extremist coffers around the world.

But the notion that they were behind 9/11 is absurd, and the proposed legislation is a terrible idea for several other reasons.

First, in foreign affairs reciprocity is everything. The rule today is that a nation state has sovereign immunity, so cannot be sued without its consent. If we abandon that principle we must assume others will quickly follow suit.

Are we ready for a world in which the United States government must defend itself in court against every foreign citizen who labels our actions as “terrorism”? How many lawsuits will be brought in Iraq and Afghanistan alone?

Finally, JASTA would effectively allow any American to insert himself into foreign affairs, ignoring the fact that there are areas which should remain the sole province of government. Foreign affairs is one of them.

Managing international relations is a difficult game of tactics and leverage. Which nations do we call out publicly? Which do we confront privately? When to come down hard on a foreign power? When to let an issue pass in the interest of cooperation on something of greater importance?

Imagine juggling those considerations if all Americans could file a suit and inject themselves into our relationship with another country. We may wish for a new secretary of state, but we should not wish for 325 million of them.

I grieve with the families of those who died on 9/11. But creating a fantasy about what killed them will not help. It will not bring them back, and it will not give us better security.

Conspiracy theories may be comforting. They are also almost invariably lies.

If we must hold someone accountable for 9/11, here is the brutal truth. We are accountable. We put men and women in power who slept on watch and let the danger grow out of control. And we kept them there.

Conspiracy theories won’t keep us safe. Vigilance will.

Charles S. Faddis, president of Orion Strategic Services, LLC, is a former CIA operations officer with 20 years of experience in the conduct of intelligence operations. He is the senior intelligence editor for AND Magazine and a contributor to a wide variety of counterterrorism and homeland security journals. He is author of "Operation Hotel California." For more of his reports, Go Here Now.